This invention relates generally to illuminated analog wristwatches requiring a manually operated crown to set the timekeeping hands, and also requiring a manually operated pushbutton to illuminate the wristwatch. More particularly, the invention relates to an improvement in an illuminated analog watch of the type having a watchcase, a movement disposed in the watchcase having a gear train and hands operated by the gear train, means for illuminating the watch in response to closure of a switch, a rotatable stem slidably disposed in the movement, a crown actuator disposed on the stem external to the watchcase for manually rotating and sliding the stem, a setting pinion disposed on the stem adapted to engage the gear train when the crown is pulled from a normal "run" position to an outer "setting" position for setting the hands, and a detent spring cooperating with the stem to temporarily hold the stem in the outer setting position.
Normally, an analog wristwatch includes a crown setting mechanism with an external manually operated crown disposed in the vicinity of the three o'clock position. The crown may be pulled from its normal run position to a setting position, in which a setting pinion on the stem engages teeth on a setting gear which meshes with the gear train, so that the time indicating hands may be rotated by rotating the crown to set the time. Such an arrangement is well known in the art, and in the case of three hand watches, may also include a slip friction clutch in the gear train permitting the gears carrying the hour hand and minute hand to rotate while the seconds wheel is held stationary by a mechanical brake. An example of such an arrangement is seen in FIG. 3 of U.S. Pat. No. 4,794,576 issued Dec. 27, 1988 to Schwartz et al. and assigned to the present assignee.
Various types of early wristwatches have provided for illumination of the timekeeping indicia by incandescent bulbs, and there is a growing use of electroluminescent illumination in wristwatches. U.S. Pat. No. 4,775,964 issued Oct. 4, 1988 to Alessio et al. and assigned to the present assignee, describes an electroluminescent device adapted to serve as the dial of an analog timepiece when a pushbutton is actuated to operate switch contacts. The constructions of manually operated external pushbutton actuators adapted to close switch contacts inside the watchcase are also well known. Examples are shown in U.S. Pat. No. 3,526,088 issued Sep. 1, 1970 to H. Meitinger, U.S. Pat. No. 4,023,002 issued May 10, 1974 to P. Wuthrich et al., and U.S. Pat. No. 4,031,341 issued Jun. 21, 1977 to P. Wuthrich et al. All of the aforesaid patents are assigned to the present assignee, and illustrate various means for spring biasing the pushbuttons, while sealing the pushbutton stems against entry of moisture.
Heretofore, the hand setting mechanism has been operated by the watch crown at one location on the watchcase and the illumination of the watch has been operated by a separate pushbutton at a different location on the watch. This requires at least two external members, need for two apertures with water-tight seals and generally adds to the cost of the timepiece. The presence of two external members, one of which is seldom used, has led to the possibility of combining the functions so that they may be operated by a single external member.
Accordingly, one object of the present invention is to provide an improvement in the crown setting mechanism and the pushbutton actuator for an illuminated analog wristwatch.
Another object of the invention is to provide an improved combined crown and pushbutton for an illuminated analog watch.